Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden, and it does disclose two genuinely useful traits beyond structured fields: the call is free (0 credits) and account scoping comes from the authenticated key (so no account parameter is needed). However, it says nothing about the shape of the returned data, pagination, or whether the read is cached/live, which matters since there is no output schema.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.